<template>
  <div class="login-container">
    <!-- 导航栏 -->
    <van-nav-bar class="page-nav-bar" title="登录">
      <van-icon slot="left" name="cross" @click="$router.back()"></van-icon>
    </van-nav-bar>
    <!-- 登录表单 -->
    <!-- 表单验证： -->
    <!-- 1.给van-field 组件配置 rules 验证规则 
    规则参考https://vant-contrib.gitee.io/vant/v2/#/zh-CN/form#rule-shu-ju-jie-gou-->
    <!-- 2.当表单提交的时候会自动触发表单验证
    如果验证通过，会触发 submit 事件
    如果验证失败，不会触发 submit -->
    <van-form ref="loginForm" @submit="onSubmit">
      <van-field v-model="user.mobile" name="mobile" 
      placeholder="请输入手机号" 
      :rules="userFormRules.mobile"
      type="number" maxlength="11">
        <i slot="left-icon" class="toutiao toutiao-shouji"></i>
      </van-field>
      <van-field v-model="user.code" name="code" 
      placeholder="请输入验证码"
      :rules="userFormRules.code"
      type="number" maxlength="6">
        <i slot="left-icon" class="toutiao toutiao-yanzhengma"></i>
        <template #button>
          <!-- time: 倒计时时间 -->
          <van-count-down v-if="isCountDownShow" 
          :time="1000*60" format="ss s"
          @finish="isCountDownShow=false"/>
          <van-button v-else class="send-sms-btn" native-type="button"
          round size="small" type="default"
          @click="onSendSms" >
          发送验证码</van-button>
        </template>
      </van-field>
      <div class="login-btn-wrap">
        <van-button class="login-btn" block type="info" native-type="submit">登录</van-button>
      </div>
    </van-form>
  </div>
</template>

<script>
import { login, sendSms } from "@/api/user";
export default {
  name: "Login",
  data() {
    return {
      user: {
        mobile: "13911111111", //手机号
        code: "246810" //验证码
      },
      userFormRules: {
        mobile: [{ 
          required: true,
          message: '手机号不能为空'
        }, {
          pattern: /^1[3|5|7|8]\d{9}$/,
          message: '手机号格式错误'
        }],
        code: [{ 
          required: true,
          message: '验证码不能为空'
        }, {
          pattern: /^\d{6}$/,
          message: '验证码格式错误'
        }]
      },
      isCountDownShow: false //是否展示倒计时
    }
  },
  methods: {
    // 表单提交事件
    async onSubmit() {
      // 1.获取表单数据
      const user = this.user;
      // 2.表单验证
      this.$toast.loading({
        message: "加载中...",
        forbidClick: true,//禁用背景点击
        duration: 0 //持续时间，默认是2000，如果为0就是持续展示
      })
      // 3.提交表单请求登录
      try {
        const res = await login(user)
        console.log("登陆成功", res)
        this.$toast.success('登录成功')
        this.$store.commit('setUser',res.data.data)
        // 登录成功，跳转回原来的页面
        // back的方式不严谨，后面讲功能优化的时候再说
        if (this.$route.query.backpage) {
          this.$router.push(this.$route.query.backpage)
        } else {
          this.$router.back()
        }
      } catch (err) {
        if (err.response.status === 400) {
          this.$toast.fail("手机号或者验证码错误")
        } else {
          this.$toast.fail("登录失败,未知错误")
        }
      }
      // 4.根据请求响应结果处理后续操作
    },
    async onSendSms (){
      // console.log('onSend')
      // 1.校验手机号
      try {
        await this.$refs.loginForm.validate('mobile')
        console.log('验证成功')
      } catch (err) {
        return console.log('验证失败',err)
      }
      // 2.验证通过，显示倒计时
      this.isCountDownShow = true
      // 3.请求发送验证码
      try {
        await sendSms(this.user.mobile)
        this.$toast('发送成功')
      } catch (err) {
        // 发送失败，关闭倒计时
        this.isCountDownShow = false
        if (err.response.status === 429) {
          this.$toast('发送太频繁，请稍后重试')
        }
        this.$toast('发送失败，未知错误',err)
      }
    }
  }
};
</script>

<style scoped lang="less">
.login-container {
  .toutiao {
    font-size: 37px;
  }
  .send-sms-btn {
    width: 165px;
    height: 46px;
    line-height: 46px;
    background-color: #ededed;
    font-size: 22px;
    color: #666;
  }
  .login-btn-wrap {
    padding: 53px 33px;
    .login-btn {
      background-color: #6db4fb;
      border: none;
    }
  }
}
</style>